Vehicle Interface Unit (VIU) Control Module - C1

2001 Chevrolet C3500 HD 8.1 G, AutomaticSECTION Vehicle Interface Unit (VIU) Control Module - C1
Vehicle Interface Unit (VIU) Control Module - C1

GM258912
Connector Part Information
  • 12110113
  • 32-Way F Micro-Pack 100 Series (RED)
Pin Wire Color Circuit No. Function
A1 - - Not Used
A2 ORN 1044 Radio Class 2 Serial Data
A3 DK GRN 835 Entertainment and Comfort Serial Data
A4-A5 - - Not Used
A6 BLK/WHT 372 Remote Radio Audio Output (-)
A7 DK GRN/WHT 368 Remote Radio Right Audio Signal
A8 BRN/WHT 367 Remote Radio Left Audio Signal
A9 BARE 814 Drain Wire
A10 LT BLU 1235 Audio Low Reference
A11 BRN/WHT 2506 Audio Return Signal
A12 DK GRN/WHT 2507 Audio Transmit Signal
A13 BARE 1792 Drain Wire
A14 GRY/BLK 2508 Microphone Signal
A15 BARE 1782 Drain Wire
A16 ORN 2540 Battery Positive Voltage
B1-B8 - - Not Used
B9 GRY 655 Cellular Telephone Microphone Signal
B10 BARE 1705 Drain Wire
B11 TAN/BLK 2510 OnStar Serial Data Return
B12 DK BLU/WHT 2511 OnStar Serial Data (-)
B13 LT BLU/BLK 2512 OnStar Serial Data (+)
B14 GRY 2520 Transceiver Low Reference
B15 PPL/WHT 2513 Ignition ON Signal
B16 - - Not Used
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.